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121.
The interest and demand for healthy and less processed foods for human consumption have been mirrored in the pet industry, with an explosion of alternative diets available. Several nontraditional feeding methodologies including raw meat-based diets (RMBDs) are believed by many dog owners to be superior to traditional extruded commercial dog foods. Despite the strong opinions, limited data are available comparing objective health measures among healthy dogs fed using different methods of diet preparation. Therefore, we compared health markers in client-owned dogs fed an RMBD to markers in dogs fed a high-quality extruded kibble. We hypothesized that healthy adult dogs fed RMBD would show differences in biochemical and hematological parameters and improved clinical health scores (e.g., dental, external ear canal, and integument scores) compared with dogs fed a kibble diet. A cross-sectional observational study was performed comparing hematology, serum biochemistry, urinalysis management history, and clinical health scores in healthy client-owned dogs reported as fed RMBD (n = 28) or kibble (n = 27) for >1 yr. Dental, external ear canal, and integument health scores were assigned by a single veterinary evaluator blinded to feed group, using a scale where 0 was normal and 3 was most severely affected. Spearman correlation coefficient (rs) was calculated to assess the strength and direction of the relationship of biochemical outcomes with age and body condition score (BCS), while analysis of variance was used to determine if biochemical analytes differed by breed or gender. Biochemical data were analyzed using multiple linear regression models, adjusting for the covariates gender, breed, age, and BCS. A composite clinical health score, (CCS) = 9 − (dental score + otitis score + integument score), was compared between feeding groups using Mann–Whitney test. Serum alkaline phosphatase activity (P < 0.001) and globulin concentration (P < 0.001) were lower, while lymphocyte count (P < 0.05) was higher in dogs fed RMBD. No differences were found in urinalysis between diet groups. Dogs fed RMBD showed a slight improvement in CCS compared with kibble-fed dogs (CCS: P = 0.03). Owner management significantly differed with a greater likelihood of management interventions including dietary supplements and sporting activities in the RMBD group. Further work is needed to specifically determine the impact of diet processing and nutrient content on canine health.  相似文献   
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In most arid and semiarid soils, naturally occurring phosphorus(P) is a major yield-limiting plant nutrient. In this study, to investigate the effects of organic(OP) and inorganic P(IP) sources on P fractionation, a calcareous sandy loam alkaline soil was fertilized with OP and IP fertilizers at low(80 mg P kg~(-1) soil) and high(160 mg P kg~(-1) soil) application rates. Three combinations of OP and IP(i.e., 75% OP + 25% IP, 50% OP + 50% IP, and 25% OP + 75% IP) were applied at low and high application rates,respectively, followed by soil aging for 21 d. Soil samples were collected after 1, 2, 3, 7, and 21 d and subjected to sequential extraction to analyze soluble and exchangeable, Fe-and Al-bound, Ca-bound, and residual P fractions. The soluble and exchangeable P fraction significantly increased up to 24.3%, whereas the Ca-bound fraction decreased up to 40.7% in the soils receiving 75% OP + 25% IP and 50% OP + 50% IP, respectively, compared with the control(receiving no P fertilizer). However, the transformation of P fractions was influenced by aging time. Addition of P sources caused instant changes in different P fractions, which then tended to decline with aging time. Change in soil p H was the limiting factor in controlling P availability. At high application rate, the OP source significantly increased soil P availability compared with the IP source with soil aging. Depending on P fractionation, a proper combination of OP and IP fertilizers, as long-term slow and instant P-releasing sources for plant uptake, respectively, may be a sustainable strategy to meet crop P requirements in the arid and semiarid soils.  相似文献   
124.
天山博格达南部雪鸡的生态习性   总被引:3,自引:1,他引:3  
新疆是雪鸡属分布的中心地区,共有3种,约9个亚种。雪鸡属是我国2级保护动物,是高山珍贵鸟类。有一定的经济价值和药用价值,在天山、昆仑山,阿尔泰山等山地的冰雪带,苔藓地带,高山草甸带,亚高山草甸带,森林带,灌木草原带等范围活动。本文阐述了新疆暗腹雪鸡的生态习性,与人工驯养繁殖实验结果。  相似文献   
125.
Common carp, Cyprinus carpio (13.54 ± 0.48 g), were fed soybean lecithin‐incorporated diets for 8 weeks. After the feeding trials, the different groups of fishes were assessed by survival, growth parameters, digestive enzymes, antioxidant enzyme activities, mucosal immune parameters, etc. The lecithin‐incorporated diets (10–30 g kg–1) helped to increase the weight gain significantly (p < .05) compared with control groups; activity of digestive enzymes was also significantly (p < .05) higher compared with experimental groups. The antioxidant enzymes including catalase and serum superoxide dismutase were significantly (p < .05) higher in the C. carpio fed lecithin‐incorporated feed than the ones fed the control feed. The serum thiobarbituric acid‐reactive substances and serum glutathione peroxidase activity did not differ significantly (p > .05) between control and experimental groups. The positive correlation supported that antibacterial activity was significantly (p < .05) increased with increasing concentration of lecithin in the diets. Among the different mucosal immune parameters, lysozyme, protease and esterase activities were significantly (p < .05) increased with lecithin‐incorporated diets. The results of this study confirm that 20 and 30 g kg–1 lecithin inclusion in diets helped to enhance the activities of digestive enzymes, antioxidant enzymes, antibacterial factors and mucosal immune parameters in C. carpio.  相似文献   
126.
Atlantic salmon post‐smolts of an average of 940 g were fed six diets including two marine‐based commercial diets one with partial inclusion of vegetable proteins (VPs) and oils (VOs) (2011/12 EU standards) (MB) and a second with partial inclusion of VPs, land animal‐by‐product (ABP) proteins and VOs (non‐EU standards) (MBABP), a fully vegetable protein (VP) diet; a fully algal and VOs (VO) diet; a fishery‐free vegetable‐based (VP/VO) diet; and a fishery‐free diet with a mix of VPs and ABP proteins and a mix of algal and vegetable oils (MFABP). Growth was assessed at Days 104 and 175, whereas fillet proximate composition, haematology and innate immune responses were assessed upon termination. Overall, MB salmon was the best performing group for the full period in terms of feed intake and overall weight gain. MB and VP salmon exhibited the highest FCRs compared to the other groups, while VP salmon exhibited the highest condition factor (K) and VO salmon the lowest K compared to the other groups. Fillet proximate composition did not present differences among the six groups. MB salmon demonstrated the highest plasma lysozyme activity compared to the other groups while MFABP, VP and VP/VO salmon demonstrated higher plasma anti‐protease activity in contrast to MB salmon. The dietary groups did not present differences in plasma protein, total IgM or natural haemolytic activity while unaltered head kidney macrophage respiratory burst activity was also observed. Overall, diets free from marine proteins or oils and/or both were satisfactorily utilized by salmon without compromising their immune capacity, although longer adaptation periods are required.  相似文献   
127.
Two hundred and thirty six semen samples were collected from 120 bulls, 60 buffalo-bulls, and 56 rams located on farms of known history of infection with Chlamydophila species. All semen samples were examined by polymerase chain reaction (PCR) and cell culture techniques for detection of Chlamydophila species. The primers were selected to allow the amplification of all target species in a single reaction by identifying conserved sequences in the omp2 gene. PCR assay detected more positive samples (36) from the semen samples collected from different animal species than were detected by the culture method (21). The results indicated that all culture-positive semen samples (21) from different species were PCR positive. The detection limit of the PCR assay was determined with DNA extracted from fourfold serial dilution of C. abortus (B577) and C. pecorum (11/88) cultures and found to be 0.25 inclusion-forming units (IFU) per PCR, while the culture method could not detect less than 4 IFU. This is the first report using PCR for the detection of Chlamydophila species in buffalo-bulls' semen and the assay provides a simple, sensitive, rapid, and reliable means for the detection and identification of the organism.  相似文献   
128.
This study was designed to assess the potential effects of Astragalus membranaceus (AM) on the growth performance and antioxidative stress response in bluegill sunfish (Lepomis macrochirus) exposed to challenging cold water temperature conditions. In this regard, fish with an average weight of 43 ± 1 g were divided into four groups and fed daily with an AM-free diet (control), and 1.5, 3, and 4.5 % (w/w) AM-incorporated diets for an 8-week period. Oxidative stress response, biochemical, and growth parameters were measured, and subgroups of fish were exposed to the outside challenging cold pond water temperature (1.6–9.9 °C) with an average of 7.0 ± 0.1 °C beyond the optimal temperature. The results showed that incorporating AM in the diet significantly improved growth performance parameters (body mass gain, specific growth rate, length, condition factor, and feed conversion ratio) and biochemicals (aspartate aminotransferase and alanine transaminase activities, and glucose and cortisol concentrations). In addition, markedly up-regulated superoxide dismutase, glutathione peroxidase, and catalase activities were observed in AM-treated fish groups over the control. Conclusively, feeding AM diets significantly increased (P < 0.05) growth performance and antioxidative stress profiles throughout the entire experiment, and this increase was much more pronounced at 8 weeks after the water temperature began to rise, which can be related to the nature of Bluegill fish as it is known to be a warm water fish. These findings are considered to be of great importance for sustainable aquaculture.  相似文献   
129.
130.
Sparus aurata were cultured during an 8-month period in brackish water (salinity about 25 ppt) in an extensive culture system comprising eight earthen ponds, each with a water surface of 2.1 ha. Initial mean wet weight of fish in all ponds varied from 13.6 ± 1.9 to 19.2 ± 2.6 g/fish. The eight ponds were randomly allocated one of four experimental treatments (two ponds/treatment). In the first treatment, ponds were fertilized monthly with 100 kg urea and 50 kg triple super phosphate. The other treatments (2–4) were fed a locally produced tilapia pellet feed containing 25% crude protein made using different processes. Fish in the second treatment were fed tilapia feed pelleted by compressing machine, whereas in treatments 3 and 4 the pellets were produced by extruder machine (Wenger). Pellets in treatment 3 were floating and in the fourth were semi-sinking. Fish were fed pellets twice daily at 6% of their biomass. The mean final body weight for each treatment respectively was 104.6, 118.9, 156.8 and 158 g. Specific growth rate (SGR) of 0.8, 0.79, 0.99 and 0.95%/day, were obtained in ponds using only inorganic fertilizer, compressed sinking pellets, extruded floating pellets and extruded semi-sinking pellets, respectively. Feed conversion ratios (FCR) for treatments with the extruded tilapia pellets were 2.2 and 2.6 g feed/g gain, which were significantly (P < 0.05) better than treatments with compressed pellets (3.2 g feed/g gain). Production/ha/year were 1389, 1358, 945 and 682 kg fish for the groups fed with extruded floating, extruded semi-sinking, compressed and natural food, respectively. Under the present experimental circumstances, Sparus aurata fed extruded floating tilapia pellets (25% crude protein and 2,600 kcal/g), showed the best productive performance.  相似文献   
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